Consequences don’t always appear immediately; sometimes, it takes years!
Fourteen years after a gunshot injury to the left knee, a 46-year-old man presented to the emergency department with complaints of progressively worsening pain in his left knee. At the time of the gunshot injury, he was not operated, so the bullet was not removed. However, the radiographs had shown a metallic bullet in the posterior weight-bearing surface of the lateral femoral condyle and metallic debris within the joint (Panel A). after 14 years, he experienced pain in the same knee.
The patient had no other symptoms of chronic lead poisoning.
On physical examination, a large effusion was noticed in the left knee. Radiography of the left knee showed metallic particles of the bullet that had fragmented.
At the current presentation, the physical examination was notable for a large effusion in the left knee. Repeat radiographs showed that the bullet had fragmented into metallic particles and spread throughout the joint and synovium (Panel B). The radiograph also showed arthritic changes in the joint.
Serological investigations revealed microcytic anemia with a hemoglobin level of 9.1 g per deciliter (normal range, 12.9 to 16.8), and an elevated blood lead level (182 μg per deciliter [8.8 μmol per liter]).
On Mini-Mental State Examination (MME), he scored 24 out of 30, where 0 is the least score and 30 is the best (lower scores indicating poorer cognitive performance).
Ideally, at the time of gunshot injury, the retained bullet in the joint (intraarticular bullet) should be removed surgically because the bullet can damage the joint, fragment, and dissolve in the synovial fluid, leading to lead absorption and delayed symptomatic lead poisoning. Although quite rarely reported, lead intoxication or plumbism from retained bullets can be fatal if left untreated.
Plumbism can present insidiously with unexplained anemia, abdominal pain/colic, kidney diseases, and neurological manifestations. The patient may remain asymptomatic unless there is a precipitating event such as infection, metabolic stress, alcoholism, etc.
Chelation therapy is imperative prior to surgery, so the patient was started on chelation therapy. Synovectomy of the left knee was planned, but the patient left the hospital before surgery and was lost to follow-up.
Jose I. Marquez, M. a. (2018, December 20). Lead Toxicity from a Retained Bullet. Retrieved from The New England Journal of Medicine: https://www.nejm.org/doi/full/10.1056/NEJMicm1804726
Linden MA, Manton WI, Stewart RM, Thal ER, Feit H. Lead poisoning from retained bullets. Pathogenesis, diagnosis, and management. Ann Surg. 1982;195(3):305-313. DOI:10.1097/00000658-198203000-00010